For anyone wondering: yes, the 18Z GFS forecast showing 20°C at 10 hPa is at the extreme end of how hot it gets at 10 hPa (caveat being this is 1.5° reanalysis against 0.25° model data).

Interesting times ahead, though still very uncertain whether a major SSW will occur. pic.twitter.com/sI0nBsnww0

— Dr Simon Lee (@SimonLeeWx) January 17, 2023